Molecularly imprinted polymer on cotton materials as substrates for smartphone-based image and distance-based analysis of Cu(II) in water samples.

Cotton fabric was used as a substrate for smartphone-based image analysis of Cu(II) in drinking water. To enhance its selective and specific binding sites on the cotton surface, a molecularly imprinted polymer (MIP) was introduced using color complexes of 4-(2-pyridylazo)resorcinol-Cu(II) (PAR-Cu(II)) as the template molecule, 3-aminopropyltriethoxysilane (APTES) as the functional monomer, tetraethoxysilane (TEOS) as the crosslinker and NH as the catalyst. After achieving optimum conditions, the obtained CF-MIP/PAR-Cu(II) presented a red color, which was changed to yellow upon the removal of Cu(II) with 1.